Tubing Thicknesses on Rivs

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MikeC

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Sep 1, 2012, 4:02:24 PM9/1/12
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The website is vague regarding tubing thicknesses used. Does anyone know the exact dimensions? Just interested in data to compare my Hillborne with other bikes that I have.
 
Please don't reply with, "Doesn't matter, they all ride great" or somesuch....
 
Thanks,
 
-Mike
 
SW Ohio

lungimsam

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Sep 1, 2012, 4:11:07 PM9/1/12
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Not sur eif you mean thickness of the tube wall rubber, or what size tires the tube will work with. If the latter:
 
If you use the drop down menu on this page it gives specs for each tube size.
 
 
 

Leslie

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Sep 1, 2012, 5:05:05 PM9/1/12
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On Saturday, September 1, 2012 12:02:24 PM UTC-4, MikeC wrote:
The website is vague regarding tubing thicknesses used. Does anyone know the exact dimensions? Just interested in data to compare my Hillborne with other bikes that I have.

It varies.   When you have bikes that were built by one company but now a different one (maybe was Toyo, now built by Waterfor; or perhaps was in Taiwan, etc.); with changes along the way (sidepulls, now cantis; one top tube, now two; etc.); well, it's possible one bike has X tubing but this other one has Y tubing.   So, to simplify it, they don't 'publish' it;  if you had X tubing listed, but then Y tubing was used on a particular bike, and some potential buyer thought they just HAD to have X tubing and felt let down by Y tubing (even when Y was a better choice for them anyway), well... it's just simpler to go with generalities, and not specifics.   Don't expect a Roadeo to be an Atlantis, or vice-versa.  I wouldn't say "it doesn't matter", as rider, end use, etc., does dictate what's appropriate.   If it really matters to you, you could call and ask. 

With that said, though, sometimes, in some of the assorted accessory info that comes out from RBW, you can learn about a particular bike.

For example, http://www.cyclofiend.com/Images/rbw/rr23_pg40md.jpg shows what the proposed tubing was for the Rambouillet, a mix of TruTemper and Reynolds, heat treated where appropriate, butted where wanted, etc. However, that changed later on, and you can read more about it here:  http://www.cyclofiend.com/Images/rbw/ram_14.jpg ; now I don't know if 'my' later Ram is still that exact tubing, but it is close to that and I'm sure it's every bit as good.   My Bombadil, by contrast, W'ford built; they haven't published it, but in speaking with them, told me that it is OX Plat, straight gauge for extra strength.   

I don't have a Sam, don't know specifics about a Sam.  I've ridden a couple, they're great bikes... different 'generations' of them, but still consistent, whether or not there were changes.... but no,  I have no idea on a Sam's steel nor tubing sizes.


 
Please don't reply with, "Doesn't matter, they all ride great" or somesuch....

 Not wanting to nitpick, but I suppose I am a little -  I may not have answered your question in regards to your Sam, but I provided what I knew on Riv tubing, that it might help others that come across this subject line later... but that little tag at the end, will probably keep a lot of people from bothering to post at all, as it almost did for me.    Yeah, you might have gotten a couple of responses like that "doesn't matter, it's great" (as I said, they are great, but I understand intent should have an effect on sizing selection); but not having that on the end, might have not turned people off, who might have known and decided to not post...  FWIW....


Jim Mather

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Sep 1, 2012, 5:07:16 PM9/1/12
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I suggest sending RBW an e-mail or calling them. When I wanted the tubing specs for the Legolas and Roadeo, I asked Mark. FWIW, the Legolas and Roadeo have the same tubing for top and seat tubes, fork blades and chain stays. The Legolas downtube is slightly heavier.

jim m
wc ca

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Peter Morgano

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Sep 1, 2012, 5:13:18 PM9/1/12
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Doesn't matter, they all ride great.
:-)

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Kelly

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Sep 1, 2012, 5:41:58 PM9/1/12
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I may be wrong but I was under the impression that Rivendell specified the frame builds. So toyo or Waterford would not make a difference in tube thickness. I am aware there are differences, I just didn't think tube thickness was one of them.

Kelly

Leslie

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Sep 2, 2012, 12:15:01 AM9/2/12
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Well, yes, and no, I would think...   Yes, Grant designs the frames, pics the material, etc.   However, when a bike that was being made in Japan by Toyo was using Miyata steel, but then when RBW transfers to building at Waterford, and W'ford doesn't have Miyata but it does have a stack of OX Plat perhaps, but there's a slight difference in gauging between the two companies, well, in that case I would suspect that Grant would select/inspect/approve of a change... it would be 'different', but, Grant would ensure that it's still 'the same'.    I'm not saying going from Ram-size tubing to Atlantis-size tubing; but, just a change of source, and adjusting to ensure it meets his spec.  Maybe it doesn't change one iota, but... well, if one Bomba had X fork crown, but this Bomba over has Y fork crown, or the same on early Rams to late Rams (even all made by Toyo), well if you can change a lug style, couldn't you re-spec a tube? 

(Of course, I'm not privy to the inner workings of Riv moving locations of builds... but it seems to me, it only makes sense or is likely that there can be adjustments along the way... nothing drastic, just tweaks...)

Kelly

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Sep 2, 2012, 12:35:17 AM9/2/12
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I agree with you from year to year Leslie.  I don't know if the Atlantis for example is the same today as it was originally or if it's grown with technology or what.  I don't know about the tubing other than the implied when I buy things that the two bikes are the same "except" phrase for water bottle cages or something.  I'm curious now.. :)  Who knows the answer.

Kelly

dougP

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Sep 2, 2012, 1:34:13 AM9/2/12
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As one who routinely seriously over-thinks many things, I recognize
the syndrome. Once again, we are getting carried away. Speculating
here but my un-educated guess is that if one supplier has differenct
sources than another, GP can make any needed adjustments in spec to
the point none of us would be able to tell any difference.

Hopefully someone sent a private post to MikeC with the info he
requested. He can knock himself out comparing his Hillborne with his
other bikes. Now there's an exercise that'll take some thinking.

dougP
> >> Kelly- Hide quoted text -
>
> - Show quoted text -

lungimsam

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Sep 2, 2012, 1:44:08 AM9/2/12
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Oh. You meant steel tubing thicknesses. Sorry.

lungimsam

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Sep 2, 2012, 1:52:31 AM9/2/12
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OK, at the risk of making myself sound dumb again, but wanting to help if I can:
 
If you are talking about the outer dimensions of the tubes, I could measure my Bleriot tubes and you could have those to compare to the Sam you have.
 
But I think you are talking about wall thickness/butted dimensions? 

Bruce Herbitter

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Sep 2, 2012, 9:39:31 AM9/2/12
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The Waterford and Taiwanese Hillbornes are quickly distinguished by the appearance difference in the rear dropouts. The Taiwan bikes have forks made by a Toyo trained fabricator, Waterfords are made locally, but they look the same. Grant was clear that the quality from either location was the same. Writing RBW for specific info on YOUR bike is a best bet to satisfy your curiosity. That answer won't change how your bike rides which you should already know if you like.

In adddition to the tubing info sheet that Cyclofiend Jim linked to earlier, RBW published detailed tube specs for the Ram (Use the "Wayback" archive to view April 2007 catalog pages) . They are all Toyo built with Tohoku-Miyata tubing. Down tube and chain stays are heat treated. Tubes are thinner walled than Atlantis.I suspect Hillborne has thicker wall tubing than Ram, at least in the forks and stays.


charlie

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Sep 2, 2012, 8:35:33 PM9/2/12
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 Unless you use the heat treated super high end tubing most butted main tubes are either .8x.5x.8 or .9x.6x.9 in thickness.  A frame like the Hillborne has a slightly lighter mix of tubing than the Atlantis but heavier than the Hilsen (from the Riv site). I think Grant once wrote that the Atlantis used .9x.6x.9 dimension main tubing....regardless, it is a touring frame and suitable for loads to 275 pounds. The Hillborne previously had a load rating to about 260 and the Hilsen about 250 lbs. You don't read much about these load ratings anymore and they are pretty conservative anyway. Keep in mind that ride qualities are a blend of several elements not limited to tubing dimensions. Knowing the numbers won't really tell you much unless the other stats are the same.  I have a frame building book that states 8x5x8 tubing is suitable for riders over 200 pounds and I am talking the modern outside dimension stuff here (the kind Riv bikes have) not the small diameter 1 inch etc. stuff used years ago. I'm not sure of the fork tubing dimensions on the Hillborne but I think Grant specs them to be safe enough to last for years. 

Leslie

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Sep 8, 2012, 12:02:55 AM9/8/12
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AND, there ya go.... Straight from Grant.... Cool!

(I'm assuming everyone gets the RBW emails?)

-L

PATRICK MOORE

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Sep 8, 2012, 12:35:19 AM9/8/12
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I am curious, Grant: I ride scandalously narrow tires on my two small wheel customs and yet I find that they are surprisingly plush over smaller bumps (6" expansion cracks are another matter). 44 1/2 cm chainstays. Is it the chainstays that makes such otherwise nasty tires tolerable? ("Nasty" is self-defensive rhetoric; I like the way the new 650C X 23 Michelin Pro Race 3s climb. Must be the "Pro" and the "Race".)

Other news: my erstwhile '73 Motobecane Grand Record frameset, now gone to a better owner, was noticeably lighter than the two Rivs. Yet it handled rear loads better. Also 44-45 cm chainstays. Why is this? Not complaining but I could carry 35 lb on the rear of the Motobecane without any real wagging, while the '03 Curt with that much is much more of a handful

Noticed today that Jan says (or implies: I think I am paraphrasing correctly) that even OS tubed frames can "plane" if the dt is thicker than TT and ST. For what *that's* worth.


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Peter Morgano

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Sep 8, 2012, 12:39:57 AM9/8/12
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Oh God, not another "Planing" discussion, argh!

Garth

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Sep 8, 2012, 12:55:44 AM9/8/12
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What makes all this talk of tubes and what does to what to what meaningless is that no two people are the same !  Not only are bodies different... but our perceptions and feel for what we wish to experience are vastly different.  So in making a frame ... the one designing it has to go with their own instincts... their own passion  Passion rubs off.  If people see someone having a good time on frame ... they'll want one too.  If they don't ... they won't !   If you cannot please yourself .... you're pleasing no one :)    

Isn't that what's all about ... having fun ?  :)     

Having said that ... I guess you can even have fun talking about things like tubes even though no one "really" knows what the other means !  lol   hahahaahaha !!!!!      ... and hey ... to me that IS fun !!!   

PATRICK MOORE

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Sep 8, 2012, 12:59:12 AM9/8/12
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This attitude seems a bit too whimsical to me. I agree with Grant that the minutiae of tubing thicknesses, tensile strengths and butt lengths mean little apart from the context of the whole frame and its user, but after all, Grant doesn't build his frames out of just anything.

Patrick "resolutely punctuating in the old style, too" Moore

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ted

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Sep 8, 2012, 1:57:46 AM9/8/12
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I have a heretical theory. Thin tires are plush, if you run em soft
that is.
It seems to me that at equal pressure fatter tires ride harder than
skinnier ones.
For example, when I was riding 22c tubulars at 55 or 60 psi going up
the ridge in the local open space they were quite cushy (it takes a
lot to pinch flat a tubular).
One reason to go to a wider tire is to stop getting pinch flats when
inflating to comfortable pressures. But when you do you will need to
go to even lower pressure to get the softness you had. If you go wide
enough you get away from the pinch flats even with the reduced
pressure. Seems like the pinch flat relief gain is bigger than the
hard ride penalty, but you do end up at much lower pressure (eg 20-25
psi in 50c Quasi-Motos vs 55-60 in 22c conti-gatorskin)
Given all that I think that how wide is wide enough depends on how
much weight is on the tire. Lighter riders (not loaded touring) can be
perfectly comfy on thiner tires than heavy folks without getting pinch
flats.

Of course there are other features of fatter tires, but for ride
quality I don't buy it being as simple as fat is comfy.

ian connelly

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Sep 8, 2012, 2:32:57 AM9/8/12
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Everyone who likes (vintage articles about) lugged steel frames and debates about tubing diameter should read this 1987 article linked via Bruce Gordon (who made both the bikes in the best):

http://www.bgcycles.com/frame-tubing-selection.html

dougP

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Sep 8, 2012, 3:28:06 AM9/8/12
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As both BG & GP point out, the art of design has been fine tuned over
decades. The recognizable names making steel frames today have
probably thousands of frames each in their experience. They know what
they're doing. Spend your time on the fun stuff like picking out the
ideal parts for your own bike.

A question just occurred to me: So you get all this info about tubing
diameters, thicknesses, strengths, etc. What do you do with it? It's
not really info you can act upon. Grant's e-mail puts it into
perspective. With 37 years experience, he got fresh input from an
ironworker.

dougP

Peter Morgano

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Sep 8, 2012, 3:39:22 AM9/8/12
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Very true, outside of full custom status the tubing mix means litltle outside of coffee talk with our friends.  I love my bombadil, and I loved my 531 bikes but I find I can ride the bombadil without worrying about flexing it to the max under my generous body while still getting a "lively" ride.

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Michael_S

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Sep 8, 2012, 4:03:18 AM9/8/12
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I think it helps you pick the bike that you want. Touring, the Atlantis has thicker tubes, fast road... the Roadeo has thinner tubes... Bomber trail bike... the Bombadil has the thickest.   You factor in your body weight, what you want to carry and pick the bike that meets those needs. Diameter and wall thickness still matter... it's the other stuff that is less important. Although heat treating is important on thin tubes... on the rest it is inconsequential. 

As most metallurgist's will tell you it's usually joints and manufacturing flaws that fail, not the parent material if it is designed correctly. 

~mike
Carlsbad Ca.


On Saturday, September 1, 2012 9:02:24 AM UTC-7, MikeC wrote:

Peter Morgano

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Sep 8, 2012, 4:18:04 AM9/8/12
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I have luckily never had a failure on a bike but  I have to say the bike i pushed to the max was a Nishiki Cresta that between me and my daughter and some stuff weighed in at over 300lbs. Cant say it rode like a dream but it did open my eyes that many bikes back in the day that were billed for "touring" were really just sport touring bikes that could not handle a load like that. My bombadil rides comfortably with alot more weight than that, which I have to put to tubing mix so you are right that it makes a difference but  I trust Grant when he says "heavy duty" for bombadil or "light tourer" for the San Marcos so I dont need to know the exact stats for each tube. Now I just wish my did didnt get me sick so I could ride, damn first week of school, every year!

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jimD

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Sep 8, 2012, 4:38:37 AM9/8/12
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Sure, that's one way to go about it. 

Me, I'm not much of an amateur bike designer.
I'm not so much interested in picking the tubes as having the person that designs the bike 
making such determinations.

When I got my Riv custom I had a conversation with Grant about my riding. He took care of the design.
He's the 'pro from Dover' when it comes to Rivendell bikes. 
My Riv custom is the best bike I've ever ridden.

Richard Sachs has been known to use the term 'gestalt' in regards to bike designs. I enjoy hearing all the discussions
about 'feeds and speeds' but compared to the folks who make their living making these things I'm a babe in the woods.

That's my story and I'm sticking to it.

-JImD

Philip Williamson

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Sep 8, 2012, 6:18:01 AM9/8/12
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Am I the only one who snickered to himself when he saw the title "belliesandbutts.pdf?"
I am, aren't I?

Philip
www.biketinker.com

Matthew J

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Sep 8, 2012, 10:38:11 AM9/8/12
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Doug: I think you are getting at GP's point. A lot people hoping to be serious cyclists or what not convince themselves they need certain tube ratios or other obscure build details. Who knows? Maybe they will wind up with a bike that makes them happy. Odds are it is not the tubing spec that brought this about.

Will

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Sep 8, 2012, 12:04:46 PM9/8/12
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I'd be interested to know if the testers swapped wheels on the test frames.

Pondero

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Sep 8, 2012, 1:11:23 PM9/8/12
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Perhaps, at one extreme we might have a perspective that only bicycle designers have the knowledge and experience to think about frame tubing, and the buyer should choose the frame simply on the basis of what the designer proclaims about about his design intent.  At another extreme, we might have the buyer educating himself to a point where he feels satisfied that he can specify his tubing for the builder to use and achieve the desired riding characteristics.  Somewhere in the middle, it seems reasonable that a buyer could actually understand some of the general impacts of changes in diameter and lighter versus heavier tubes, and do his own experiments.  

For example, as a relatively small guy, I have experimented over the years to learn that smaller diameter, lighter tubes feel better to me for my non camping rides. 

Michael Hechmer

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Sep 8, 2012, 2:19:02 PM9/8/12
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I'm a bit late to this discussion, and just went out and read GP's blog posting.  I thought it was very interesting and pretty much on the mark.  I'd like to offer a data point.

In 1983 I bought a Trek 620, which was billed as a "touring" bike but was really a sport-touring bike made with Reynolds 531C, which I have always assumed was 1/7/1.  Later I swapped it for a 1984 & larger size, which I still have and ride.  In 1988 I bought a custom Marinoni stage racing bike, which has Columbus tubing. Probably 9/6/9 but I'm not certain.  I'd never heard GPs claim that people advertised Reynolds for touring and Columbus for criterium but I have to say my experience suggests that is imaginary.  Both of these bikes ride very nicely, both are responsive, both climb and descend solidly, both have excellent road manners.  The Trek has mostly been ridden on 32 mm clinchers and the Marinoni on 21 mm tubulars, so the rides do differ.  Whatever difference there are in the performance of these two bikes I doubt if many people could ever identify them as fame material.  In 2004 I bought a Rambouillet, which has OS tubing.  And I would say the ride especially with light weight wheels and tires is extraordinarily similar to the Marinoni - it just has a bit slower handling, more tire clearance and braze ons.  Again, tube thickness doesn't seem to make any difference at all.  I also have a 1999 SOMA Dbl Cross, which is noticeably heavier & stiffer tubing.  It definitely rides differently than he others.  I have a newer Ebisu All Purpose, with geometry quite similar to the AHH.  It is stiffer, with slower handling, especially at slower speed,which I found to be a great advantage while commuting with it.  But it does not respond the way the Ram, Marinoni or even the Trek does.  So, as has been said, at some point tubing can help make a bike more stable under load or more responsive in a sprint, but the slight difference between quality mfgs. or a mm on the butt is going to disappear very quickly in real world useage.

Michael

Michael Hechmer

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Sep 8, 2012, 2:20:06 PM9/8/12
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Bill M.

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Sep 8, 2012, 2:28:48 PM9/8/12
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Grant says:
"Talk of frame tubing and stiffness always leads to this: Two tubes of identical diameter and wall thicknesses will be equally stiff regardless of the tensile strength of the tube. Heat-treating doesn’t affect stiffness, and neither does tensile strength. This is what is said. Metallurgists have locked it in. I’ve been deep into bikes for 37 years and I’ve read it a hundred times, written it fifteen, and said it right around eighty, but I don’t believe it anymore.

My Pal Jeff is an ironworker, and about ten years he was talking about how rebar comes in different diameters and strengths, and if you were bending a dozen or more lengths of rebar of a given strength and diameter, and then a stronger one of the same diameter sneaked into the pile without you knowing it, it took twice the force to bend it.

This was disturbing to hear because it violated what I had locked in and told to others. I’ve thought a lot about it a lot but it didn’t seem scientific enough to repeat, and then about a year ago I read a sciency source saying something like hey, maybe tubes and rods of identical dimensions bend differently after all, and that’s what it took to switch me over.

 Some metallurgists will squawk at the suggestion that strength affects stiffness, but when the rebar bender with (in some cases) an eighth-grade education and twenty years of experience on thousands of rods picks up a rogue lookalike and says darn, Jeff, I can’t bend this son-of-a-gun, he is doesn’t have a reputation to defend, has nothing to lose one way or the other and doesn’t give a hoot, so you should listen….and try for yourself, and you’ll see it’s the same."


Sorry, gotta rant a little:

The conclusion Grant reaches here is not correct. Metallurgists do know what they are talking about. His example only proves how easy it is to confuse stiffness with strength.  Using the example of bending a piece of steel is irrelevant and misleading.   We don't bend steel frames by riding them.   Tubes used in a bike frame are sized so that they never reach the yield point.  Under all normal riding loads  they spring back, they do not permanently deform like the rebar Pal Jeff was bending.  

The stiffness of the two pieces of rebar (the 'regular' and the 'stronger') are the same up to the point at which they begin to permanently deform.  For the regular rebar, it takes relatively little force to reach that point.  Once the metal starts to deform, the force it takes to continue bending it does not go up, and at some point it actually decreases.  That makes it feel soft.  The stronger bar isn't any stiffer, but its higher yield strength means it can be bent a lot further before it starts to deform.  It takes a lot more force to bend that bar far enough to yield.  That does not mean it is stiffer, that means it is stronger!  

The coil springs in an auto suspension are made from steel that's roughly as thick as rebar, but they can bend a long way and spring back.  That's because they are made from much higher strength steel.  Rebar would make a lousy spring, it would compress once and not spring back.  Again, that's due to strength, not stiffness.  Our steel bike frames are built more like springs than they are rebar.

I think Grant has undermined his point, that given reasonable metallurgy (CR-MO steel or an equivalent), and in tubing gauges that will make a bike ride well, ultimate strength is not usually a factor.  It can start to matter if the tubes get really thin walled, but Grant doesn't tend to build that way.  A plain gauge tube can be perfectly good if the goal is to increase the stiffness of the tube (which a thicker middle section will do) and the thickness at the joint is sufficient for strength.  Butting is needed when the tube belly is too thin to make a strong joint.  That's all fine and sensible.  There's no need to ignore scientific facts to get there.

Rant over.

Bill Mennuti
Stockton, CA

charlie

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Sep 8, 2012, 3:35:06 PM9/8/12
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This makes sense and lines up with my reading on the subject over the years...... strength vs. stiffness etc. Our frames really are 'springs' in that they don't go past the yield point. This is why we like steel it doesn't fail like aluminum does.Thin walled tubing is great for lighter loads as it is essentially a lighter spring. Put a big enough load/rider on a Rodeo and it will feel like a piece of 'wet spaghetti' (definitely), same applies if a flyweight rides a Bombadil he'll feel like its too stiff and unyielding (maybe). I'm thinking the dent resistance of heavier walled tubing is a smart idea especially on the top tube when it gets leaned up against stuff and sometimes the handlebar end twists and whacks it, putting a dent in it. Beyond all this what we are talking about are just bicycle frames and I figure Grant and his builders have more experience in the area than I ever will plus he has a vested interest in making a good and safe product. .9x.6x.9,.8x.5x.8, straight .8 or even1.0x.7x1.0 they are just tubes that require a good fit, proper joints and intelligent design. Thanks Grant, for the article you emailed. You have my confidence. 

Michael_S

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Sep 8, 2012, 4:06:33 PM9/8/12
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I guess I really like knowing those details and researching and learning about frame design and such. I spent 31 years in the high tech metals industry ( Rocket Engines) doing exactly this, so it comes natural to want to understand. On the customs I have bought I provided key design characteristics for the frame and selected the tubing to meet my needs and planned use.  To me that was a best part of buying a custom  frame.

~mike
Carlsbad Ca.
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